1. Field of the Invention
The present invention relates to doors for operator compartments of industrial vehicles, and more specifically to a new and improved dual action door handle and release mechanism that can be used for one or both of (a) allowing a door of a cab of an industrial vehicle to be released from an intermediary position so that it may be swung wide open, and/or (b) releasing such a door that has been propped wide open so that it may be easily closed, both operations being possible from inside or outside of the cab.
2. Description of the Prior Art
Vehicles, particularly industrial vehicles, ordinarily include an operator compartment or cab which contains a seat for the operator, and controls for operating the vehicle. Cabs are often enclosed for safety reasons, noise reduction, protection from adverse weather conditions and the like. Such cabs are typically positioned above the main chassis of the vehicle such that the operator must step or climb up in order to enter the cab. Hand rails and/or steps may be provided on the outside of the cab to assist the operator in climbing into the cab. Typically, one or more hingedly mounted doors are provided on a side of the cab through which the operator may gain entry. An exterior latching handle on such a door is used to open it.
For many cab doors, once the door has been opened, it is free to swing on its hinges through an arc that is sufficiently wide to allow an operator to enter the cab through the open door. In many cabs, it is generally unnecessary for the door to swing open beyond an arc of about 90 degrees, since this is usually sufficient for the operator to gain access. As a result, door latches have been developed that prevent the door from opening beyond about 90 degrees without further operator intervention. In many cases a release latch must be operated if the door is to be opened beyond 90 degrees.
During use of the industrial vehicle, it may be desirable for the door to be propped open for cooling, ventilation, loading, repair or the like. In these situations, the operator must operate a first latch release, unlatching the door and allowing it to open as wide as 180 degrees, bringing the door against the side of the cab. An intermediate stop may be provided at around 90 degrees, so that the door does not swing completely open, allowing an operator to easily close the door after entering the cab. A coupling is typically provided on the door which engages a mating surface on the side of the cab to hold the door wide open, if desired, against the side of the cab (door holdback) until the coupling is released. A typical coupling release mechanism is provided in the form of a button or lever located on the inside of the cab in the vicinity of the mating surface. This allows an operator inside the cab to push the button/lever in order to release the coupling and allow the door to swing freely so that it may be closed. As such a door is closed, an intermediate latch may engage the door when it has closed to within about 90 degrees, as disclosed in U.S. Pat. No. 7,096,538, requiring the operator to operate another release in order to fully close the door. As a result, simply closing the door may require the operator to operate two release mechanisms.
In many cases, the vehicle operator will exit and descend from the cab while the door is propped open and coupled to the side of the cab. Then, in order to release the door to close it, the operator must climb back up into the cab and then reach into the back of the cab in order to push the button (or move the lever) to release the door from the coupling. Moreover, the operator may then also be required to release the interior latch to allow the door to fully close. It is time consuming and inconvenient for the operator to have to climb back up into the cab, and to operate two separate mechanisms just to close the door.
One patent which addresses this situation is U.S. Pat. No. 5,655,798 which discloses a ground level extension from a cab level door latch that may be used to release a first latch to open the door, or release a second latch to close it. However, the extension cannot easily be reached when the door is latched in the open position since at such times the extension is sandwiched between the door and the side of the cab. An operator must reach outside of the cab in order to unlatch the latched-opened door in order to close it. In addition, nothing in this patent provides an intermediate stopping position, or otherwise prevents a partially opened (unlatched) door from swinging completely open and latching in a full open position against the side of the cab.
It is therefore desirable to provide a single release mechanism for the door of a cab of an industrial vehicle that allows a door that has been propped open to be easily closed from inside the cab, or from outside of the cab without having to climb back into the cab.